The present invention is directed to a semiconductor laser which may be either optically or electrically pumped and has a semiconductor body with a layer format having resonator mirror structures being provided on opposite end surfaces of the body and a laser active zone generating the laser radiation in response to pumping being disposed between the mirror structures and terminating at a distance from each of the mirror structures.
For semiconductor lasers or, respectively, laser diodes which, in particular, are designed for a high output power of the emitted laser radiation, it is known that there is a problem of heating the mirror surfaces of the optical resonator of the laser. This heating can considerably limit the performance capabilities of such a laser. When the maximum load allowed for heating the respective mirror surface is exceeded, there is either an abrupt ageing and destruction of the mirror or, respectively, a loss of a significant part of the reflective property. Considerable long-term ageing of the reflective properties can already be observed even at output powers that are considerably below the maximum load.
A gallium aluminum arsenide semiconductor laser, which is consctructed on the principle of "window structure" is disclosed in articles from IEEE Journ. Quantum Electr., Vol. QE 15 (1979), p. 775; and Appl. Phys. Letter, Vol. 34 (1979), p. 367, and in U.S. Pat. No. 4,349,905, whose disclosure is incorporated by reference thereto. This structure provides that the laser-active zone or, respectively, the semiconductor body in the region of this laser-active zone given a double hetero-structure injection laser is divided by topically limited zinc diffusion into short n-doped and longer p-doped length segments. The mirror surfaces are provided in the region of the n-doped segments. The absorption of the laser radiation generated in the longer p-doped segments is considerably reduced in the n-doped segments so that the thermal load of the respective mirror surfaces can be reduced. However, the structure requires a more involved manufacture process for the diode.
A laser diode is disclosed in U.S. Pat. No. 4,371,966, whose disclosure is incorporated by reference thereto. This laser diode has mirrors adjacent to the semiconductor material, that is not to be pumped, but these mirrors belong to a waveguide structure that is passive overall. Again, such a structure requires a more involved manufacture process.